This example uses a geospatial dataset of rectangular polygons to visualize named regions across South America and West Africa. It renders a map from a GeoJSON FeatureCollection, with each polygon’s properties labeling its area and name. The visualization relies on a mapping library to project and draw the geometry, while the interaction between overlapping regions (like the nested “South America Pacific” and “Atlantic” areas) is shown through distinct filled shapes. The code likely employs `d3.geoPath` for path generation and Canvas or SVG rendering, with the raw coordinate data directly defining the boundaries. The source is a gist, and the author is Fil.